A gas turbine engine generally includes a core having, in serial flow order, a compressor section, a combustion section, a turbine section, and an exhaust section. During operation, an engine airflow is provided to an inlet of the compressor section where one or more axial compressors progressively compress the air until it reaches the combustion section. Fuel is mixed with the compressed air and burned within the combustion section to provide combustion gases. The combustion gases are routed from the combustion section to the turbine section. The flow of combustion gasses through the combustion section drives the combustion section and is then routed through the exhaust section, e.g., to atmosphere.
In particular configurations, the gas turbine engine additionally includes a fan surrounded by an annular casing and positioned in flow communication with the core. The annular casing can define a bypass passage with the core. With such a configuration, a first portion of the air from the fan is provided to an inlet of the core and a second portion of the air from the fan is routed around the core through the bypass passage. In certain embodiments, bypass air from the bypass passage can subsequently be routed into the core downstream of the inlet and used as a cooling medium for one or more heat exchangers. Specifically, the core of the gas turbine engine can include one or more heat exchangers positioned therein for removing heat from, e.g., lubrication oil used in the operation of the gas turbine engine. With such a configuration, the core draws bypass air in from the bypass passage, over or into the one or more heat exchangers, and then exhausts the air back into the bypass passage.
With such a configuration, however, the one or more heat exchangers can occupy a relatively large amount of space in the core, increasing a size of the core. Efforts to increase an efficiency of the gas turbine engine, however, call for a reduction in the size of the core. Accordingly, a gas turbine engine having a reduced core size while maintaining one or more heat exchangers would be beneficial. More particularly, a gas turbine engine having one or more heat exchangers configured to occupy less space in the core would be particularly useful.